The invention relates to a weaving machine for the manufacture of leno cloths and to a method for cleaning a weaving machine.
Newer generations of weaving machines for the manufacture of leno cloths, in particular of leno cloths which serve as base fabrics for the manufacture of carpets, are being operated at increasing speeds of rotation. The increase in the speeds of rotation became possible above all through the use of airjet weft insertion systems, through which it was possible to achieve a considerable increase in performance. With this increase in performance the contamination through fiber fly also increased. In dependence on the kind of warp thread material, accumulations of fiber fly are formed in the region of the leno apparatus, more precisely at the elements of the leno apparatus, e.g. at needle bars, deflection elements or insertion rails. The fiber fly formation is particularly extreme when using fiber yarns, such as for example cotton.
In a weaving machine for the manufacture of cloths with simple warp thread systems, such as for example cloths with canvas binding and their derivatives, the warp threads cross one another at each new forming of a shed; i.e. the lower warp threads come to lie upwardly and the upper ones downwardly. Through this crossing of warp threads in the forming of a shed, large accumulations of fiber fly in the shed are largely avoided.
In the manufacture of leno cloths, in particular of semi-leno cloths, which serve as base fabrics for the manufacture of carpets, the same warp threads always lie upwardly or downwardly respectively in the shed. The ground threads and the leno threads are lifted with respect to one another after a weft insertion only to such an extent as is required for the change of side of the leno threads. The fiber fly can thus accumulate without hindrance at the elements of the leno apparatus. This is especially true of the rear region of the shed. Larger accumulations which come loose from the elements of the leno apparatus are also enclosed in the region of the shed between the ground and leno threads and can be removed from there only with difficulty.
To avoid blockages in the thread passages of the leno apparatus, as well as the thread breakages and the corresponding longer standstill times of the weaving machine resulting therefrom, the newer weaving machines for the manufacture of leno cloths must be stopped as a precautionary measure for the purpose of removing fiber fly accumulations. This is time-consuming and reduces the weaving performance. So-called travelling clearers, such as are known from the prior art, produce only an insufficient cleaning effect in the critical regions of the leno apparatus.